| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py |
| ; RUN: opt < %s -passes=mem2reg -S | FileCheck %s |
| |
| ; This tests that mem2reg preserves the !nonnull metadata on loads |
| ; from allocas that get optimized out. |
| |
| ; Check the case where the alloca in question has a single store. |
| define ptr @single_store_noundef(ptr %arg) { |
| ; CHECK-LABEL: @single_store_noundef( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8 |
| ; CHECK-NEXT: [[TMP0:%.*]] = icmp ne ptr [[ARG_LOAD]], null |
| ; CHECK-NEXT: call void @llvm.assume(i1 [[TMP0]]) |
| ; CHECK-NEXT: ret ptr [[ARG_LOAD]] |
| ; |
| entry: |
| %buf = alloca ptr |
| %arg.load = load ptr, ptr %arg, align 8 |
| store ptr %arg.load, ptr %buf, align 8 |
| %buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0 |
| ret ptr %buf.load |
| } |
| |
| define ptr @single_store_missing_noundef(ptr %arg) { |
| ; CHECK-LABEL: @single_store_missing_noundef( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8 |
| ; CHECK-NEXT: ret ptr [[ARG_LOAD]] |
| ; |
| entry: |
| %buf = alloca ptr |
| %arg.load = load ptr, ptr %arg, align 8 |
| store ptr %arg.load, ptr %buf, align 8 |
| %buf.load = load ptr, ptr %buf, !nonnull !0 |
| ret ptr %buf.load |
| } |
| |
| ; Check the case where the alloca in question has more than one |
| ; store but still within one basic block. |
| define ptr @single_block_noundef(ptr %arg) { |
| ; CHECK-LABEL: @single_block_noundef( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8 |
| ; CHECK-NEXT: [[TMP0:%.*]] = icmp ne ptr [[ARG_LOAD]], null |
| ; CHECK-NEXT: call void @llvm.assume(i1 [[TMP0]]) |
| ; CHECK-NEXT: ret ptr [[ARG_LOAD]] |
| ; |
| entry: |
| %buf = alloca ptr |
| %arg.load = load ptr, ptr %arg, align 8 |
| store ptr null, ptr %buf, align 8 |
| store ptr %arg.load, ptr %buf, align 8 |
| %buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0 |
| ret ptr %buf.load |
| } |
| |
| define ptr @single_block_missing_noundef(ptr %arg) { |
| ; CHECK-LABEL: @single_block_missing_noundef( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8 |
| ; CHECK-NEXT: ret ptr [[ARG_LOAD]] |
| ; |
| entry: |
| %buf = alloca ptr |
| %arg.load = load ptr, ptr %arg, align 8 |
| store ptr null, ptr %buf, align 8 |
| store ptr %arg.load, ptr %buf, align 8 |
| %buf.load = load ptr, ptr %buf, !nonnull !0 |
| ret ptr %buf.load |
| } |
| |
| ; Check the case where the alloca in question has more than one |
| ; store and also reads ands writes in multiple blocks. |
| define ptr @multi_block_noundef(ptr %arg) { |
| ; CHECK-LABEL: @multi_block_noundef( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8 |
| ; CHECK-NEXT: br label [[NEXT:%.*]] |
| ; CHECK: next: |
| ; CHECK-NEXT: [[TMP0:%.*]] = icmp ne ptr [[ARG_LOAD]], null |
| ; CHECK-NEXT: call void @llvm.assume(i1 [[TMP0]]) |
| ; CHECK-NEXT: ret ptr [[ARG_LOAD]] |
| ; |
| entry: |
| %buf = alloca ptr |
| %arg.load = load ptr, ptr %arg, align 8 |
| store ptr null, ptr %buf, align 8 |
| br label %next |
| next: |
| store ptr %arg.load, ptr %buf, align 8 |
| %buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0 |
| ret ptr %buf.load |
| } |
| |
| define ptr @multi_block_missing_noundef(ptr %arg) { |
| ; CHECK-LABEL: @multi_block_missing_noundef( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8 |
| ; CHECK-NEXT: br label [[NEXT:%.*]] |
| ; CHECK: next: |
| ; CHECK-NEXT: ret ptr [[ARG_LOAD]] |
| ; |
| entry: |
| %buf = alloca ptr |
| %arg.load = load ptr, ptr %arg, align 8 |
| store ptr null, ptr %buf, align 8 |
| br label %next |
| next: |
| store ptr %arg.load, ptr %buf, align 8 |
| %buf.load = load ptr, ptr %buf, !nonnull !0 |
| ret ptr %buf.load |
| } |
| |
| ; Check that we don't add an assume if it's not |
| ; necessary i.e. the value is already implied to be nonnull |
| define ptr @no_assume(ptr %arg) { |
| ; CHECK-LABEL: @no_assume( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: [[ARG_LOAD:%.*]] = load ptr, ptr [[ARG:%.*]], align 8 |
| ; CHECK-NEXT: [[CN:%.*]] = icmp ne ptr [[ARG_LOAD]], null |
| ; CHECK-NEXT: br i1 [[CN]], label [[NEXT:%.*]], label [[FIN:%.*]] |
| ; CHECK: next: |
| ; CHECK-NEXT: ret ptr [[ARG_LOAD]] |
| ; CHECK: fin: |
| ; CHECK-NEXT: ret ptr null |
| ; |
| entry: |
| %buf = alloca ptr |
| %arg.load = load ptr, ptr %arg, align 8 |
| %cn = icmp ne ptr %arg.load, null |
| br i1 %cn, label %next, label %fin |
| next: |
| ; At this point the above nonnull check ensures that |
| ; the value %arg.load is nonnull in this block and thus |
| ; we need not add the assume. |
| store ptr %arg.load, ptr %buf, align 8 |
| %buf.load = load ptr, ptr %buf, !nonnull !0 |
| ret ptr %buf.load |
| fin: |
| ret ptr null |
| } |
| |
| define ptr @no_store_single_load() { |
| ; CHECK-LABEL: @no_store_single_load( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: [[TMP0:%.*]] = icmp ne ptr undef, null |
| ; CHECK-NEXT: call void @llvm.assume(i1 [[TMP0]]) |
| ; CHECK-NEXT: ret ptr undef |
| ; |
| entry: |
| %buf = alloca ptr |
| %buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0 |
| ret ptr %buf.load |
| } |
| |
| define ptr @no_store_multiple_loads(i1 %c) { |
| ; CHECK-LABEL: @no_store_multiple_loads( |
| ; CHECK-NEXT: entry: |
| ; CHECK-NEXT: br i1 [[C:%.*]], label [[IF:%.*]], label [[ELSE:%.*]] |
| ; CHECK: if: |
| ; CHECK-NEXT: [[TMP0:%.*]] = icmp ne ptr undef, null |
| ; CHECK-NEXT: call void @llvm.assume(i1 [[TMP0]]) |
| ; CHECK-NEXT: ret ptr undef |
| ; CHECK: else: |
| ; CHECK-NEXT: [[TMP1:%.*]] = icmp ne ptr undef, null |
| ; CHECK-NEXT: call void @llvm.assume(i1 [[TMP1]]) |
| ; CHECK-NEXT: ret ptr undef |
| ; |
| entry: |
| %buf = alloca ptr |
| br i1 %c, label %if, label %else |
| |
| if: |
| %buf.load = load ptr, ptr %buf, !nonnull !0, !noundef !0 |
| ret ptr %buf.load |
| |
| else: |
| %buf.load2 = load ptr, ptr %buf, !nonnull !0, !noundef !0 |
| ret ptr %buf.load2 |
| } |
| |
| !0 = !{} |